Electronic structures, hole-doping, and superconductivity of the s = 1, 2, 3, and 4 members of the (Cu,Mo)-12s2 homologous series of superconductive copper oxides

Inga Grigoraviciute; Maarit Karppinen; Ting-Shan Chan; Ru-Shi Liu; Jin-Ming Chen; Omar Chmaissem; Hisao Yamauchi

doi:10.1021/ja9087067

Electronic structures, hole-doping, and superconductivity of the s = 1, 2, 3, and 4 members of the (Cu,Mo)-12s2 homologous series of superconductive copper oxides

J Am Chem Soc. 2010 Jan 20;132(2):838-41. doi: 10.1021/ja9087067.

Authors

Inga Grigoraviciute¹, Maarit Karppinen, Ting-Shan Chan, Ru-Shi Liu, Jin-Ming Chen, Omar Chmaissem, Hisao Yamauchi

Affiliation

¹ Materials and Structures Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan.

PMID: 20017548
DOI: 10.1021/ja9087067

Abstract

We demonstrate that the T(c) value of superconductive copper oxides does not depend on the distance between two adjacent CuO(2) planes as long as the hole-doping level and the immediate (crystal) chemical surroundings of the planes are kept the same. Experimental evidence is accomplished for the homologous series of (Cu,Mo)-12s2, the member phases of which differ from each other by the number (s) of cation layers in the fluorite-structured (Ce,Y)-[O(2)-(Ce,Y)](s-1) block between the CuO(2) planes. X-ray absorption near-edge structure spectroscopy is employed as a probe for the hole states of these phases. The s = 1 member appears to be more strongly doped with holes than other phases of the series and accordingly to possess the highest T(c) value of 87 K. For s > or = 2, unexpectedly, both the CuO(2) plane hole concentration and the value of T(c) (approximately 55 K) remain constant, being independent of s.